Heat a large saucepan or dutch oven over medium-high heat. Add pancetta cubes and sauté for 5 to 7 minutes or until brown and crispy. With a slotted spoon, transfer cooked pancetta to a paper-towel lined plate, leaving any rendered fat in the pan.
Reduce heat to medium and add onions to pan; cook until soft and translucent, about 5 to 7 minutes.
Add chopped pears, cashews, and coriander and cook for 2 minutes.
Add chicken broth and bring soup to a simmer and let simmer the soup for 5 minutes or until pears are softened.
Add spinach and parsley and simmer for 1 minute more or until spinach is completely wilted.
Remove from heat. Transfer soup to blender, working in batches if necessary, and puree until smooth and creamy (use caution when blending hot liquids).
Return to saucepan and set over medium heat to rewarm.
Season with salt and pepper to taste.
For a creamier soup, stir in ¼ cup mascarpone cheese until melted and smooth.
Divide among serving bowls. Drizzle with olive oil (if desired), and sprinkle with pancetta bits. Serve warm with crusty bread for dipping.
